1. Field of the Invention
The present invention relates to a radio receiver used in an automobile vehicle.
2. Description of the Prior Art
As a receiver for an automobile vehicle, there is known a diversity receiver in which two antennas having a directivity different from each other are employed. In this diversity receiver, the one antenna having better receiving conditions is used for reception by switching between the antennas as disclosed in, for example, Japanese Patent Publication No. 94929/1984, in order to always receive FM broadcasting, AM broadcasting and so forth under good conditions.
Such a receiver generally comprises two antennas provided adjacent to a rear trunk of a vehicle body, a receiver unit located in a compartment of the vehicle, and a feeder connecting the receiver unit to the antennas. In this constitution, there is a problem in that the receiving condition, especially the AM broadcasting receiving condition, is not good because the length of the feeder connecting the receiver unit to the antennas is very long.
In order to solve the above problem, it might be proposed to divide the receiver unit into a tuner unit (receiver main body) and an operation unit and to provide the tuner unit adjacent to the antennas. Namely, this receiving system comprises the operation unit provided in the compartment, and the tuner unit provided near the antennas and operated by the operation unit by way of remote control, and a feeder connecting between the tuner unit and the antennas.
According to this construction, it is possible to shorten the length of the feeder thereby to suppress the generation of noises during receiving. Furthermore, the required space within the compartment for the aforementioned receiver unit can be reduced since only the operation unit is located in the compartment. With regard to the connection between the tuner unit and the operation unit, the use of a multiple line is preferable to achieve simplification of the connecting wirings.
However, even if the above mentioned noises are suppressed by adopting the technique described above, the pulse signal for operating the receiver main body (tuner unit), sent thereto from the operation unit, are received as noise by the receiver main body through the antennas, and thus the pulse signal is audibly output as noise from a speaker.